Each year, approximately 500,000 surgical procedures are performed in the U.S. to promote growth of bone with bone grafts or bone substitutes. Currently available bone substitutes are far from ideal and have many associated problems. A clinical demand exists for alternative bone grafting matrices. We propose to directly create three dimensional scaffolds using a new rapid protoytping, RP, technology. Metrix's computer integrated RP system has potential for directly fabricating hierarchical, three dimensional scaffolds that can be seeded with growth factors to promote regeneration of engineered tissue. Long term goal is to develop material compositions that will allow a family of scaffolds to be produced for use as reasorbable bone substitutes and implants for targeted indications. Phase l will develop a hydrogel carrier for controlled release of rhBMP-2 growth factor and build porous hydroxyapatite ceramic/collagen composite scaffolds. Release rates will be measured on BMP-impregnated carrier, scaffold. Constructs will be evaluated through in vitro degradation studies and mechanical tests. Phase II will optimize scaffold design and composition, build and evaluate scaffolds through in vitro and then in vivo animal models for osteoconductive and osteoinductive properties, and develop capabilities for rapid design and production of resorbable bone substitutes and implants. PROPOSED COMMERCIAL APPLICATIONS: Over 450,000 bone graft procedures are done annually in the U.S. with a market potential of $400 to 600 million. Technology will provide significant improvements in indications as resorbable bone substitutes and implants include orthopeadic applications for autologous bone graft in fresh and non-union fractures, spinal fusions, and bone defects: in cranio/maxillofacial reconstruction.